• International Journal of Reliability and Applications
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• v.7 no.2
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• pp.89-99
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• 2006

A new classes of life distribution, namely harmonic used better than aged in expectation in upper tail (HUBAEUT) is introduced. Testing exponentiality against this class is investigated using kernel method. The limiting null and nonnull distribution of the test statistics is normal and the null variance is calculated exactly. Selected critical values are tabulated for sample sizes of 5(1)40. Power of the test are estimated by simulation. the efficacies of the test statistics used for testing against HUBAEUT are calculated for som common alternatives and are compared to some other procedures. It is shown that proposed test is simple, has high relative efficiency and power for some commonly used alternatives. The set of real data are used as an examples to elucidate the use of the proposed test statistics for practical reliability.

• Journal of the Korean Geotechnical Society
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• v.19 no.2
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• pp.135-146
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• 2003

Uphole test is a seismic field test using receivers on ground surface and a source in depth. In this paper, the uphole test using SPT(standard penetration test) which is economical and reliable for obtaining shear wave velocity profile was introduced. In the proposed uphole test, SPT sampler which is common in site investigation, was used as a source and several 1Hz geophones in line were used as receivers. Test procedures in field and interpretation methods for obtaining interval times and for determining shear wave velocity profile considering refracted ray path were introduced. Finally, uphole test was performed at three sites, and the applicability of the proposed uphole test was verified by comparing wave velocity profiles determined by the uphole test with the profiles determined by downhole test, SASW test and SPT-N values.

• The Journal of Advanced Prosthodontics
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• v.9 no.2
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• pp.110-117
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• 2017

PURPOSE. This laboratory study assessed the effect of different dentin cleaning procedures on shear bond strength of resin cements for recementing prosthesis. MATERIALS AND METHODS. A $4{\times}4$ flat surface was prepared on the labial surface of 52 maxillary central incisors. Metal frames ($4{\times}4{\times}1.5mm$) were cast with nickel-chromium alloy. All specimens were randomly divided into 2 groups to be cemented with either Panavia F2.0 (P) or RelyX Ultimate (U) cement. The initial shear bond strength was recorded by Universal Testing Machine at a crosshead speed of 0.5 mm/min. Debonded specimens were randomly allocated into 2 subgroups (n = 13) according to the dentin cleaning procedures for recementation. The residual cement on bonded dentin surfaces was eliminated with either pumice slurry (p) or tungsten carbide bur (c). The restorations were rebonded with the same cement and were subjected to shear test. Data failed the normality test (P < .05), thus were analyzed with Mann Whitney U-test, Wilcoxon signed rank test, and two-way ANOVA after logarithmic transformation (${\alpha}=.05$). RESULTS. The initial shear bond strength of group P was significantly higher than group U (P = .001). Pc and Uc groups presented higher bond strength after recementation compared to the initial bond strength. However, it was significant only in Pc group (P = .034). CONCLUSION. The specimens recemented with Panavia F2.0 provided higher bond strength than RelyX Ultimate cement. Moreover, a tungsten carbide bur was a more efficient method in removing the residual resin cement and increased the bond strength of Panavia F2.0 cement after recementation.

• Journal of Hospice and Palliative Care
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• v.8 no.2
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• pp.200-208
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• 2005

Purpose: Palliative procedures or surgical interventions not only manage various symptoms of malignant gastrointestinal obstruction, but also improve the quality of life. We investigated the clinical characteristics and prognostic factors of terminal cancer patients with palliative procedures for malignant gastrointestinal obstruction. Methods: We retrospectively reviewed the medical records of 48 terminal cancer patients with palliative procedures for malignant gastrointestinal obstruction at Sam Anyang hospital from May in 2002 to May in 2005. We excluded patients with palliative tumor resection. We analyzed prognostic factors in symtom-free survival and overall survival using Kaplan-Meier method, univariate and multivariate analysis. Results: There were 25 males (52%) and 23 females (48%), and median age of 48 patients was 65 years. The most common cause of malignant gastrointestinal obstruction was colorectal (26 patients, 55%), followed by stomach (10, 21%). Twenty patients (42%) received previous treatment (chemotherapy, surgery, and radiotherapy) and 28 (58%) never received any. Eighteen of 20 had received chemotherapy. The most common symptom was pain (15 patients, 31%). Twenty three patients (48%) had Eastern Cooperative Oncology Group(ECOG) performance status of 1 or 2 score and 25 patients (52%) 3 or 4 score. The most common palliative procedure was colostomy and there was no mortality concerning the palliative procedures. By univariate and multivariate analysis, performance status was the only independent prognostic factor in overall survival and symptom-free survival. Overall survival was 150 days and symptom-free survival was 90 days. Conclusion:. We confirmed that perftatdormance status is significant independent prognostic factor in terminal cancer patients with palliative procedures for malignant gastrointestinal obstruction.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.5
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• pp.77-83
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• 2008

Semi-active cabin air suspension system improves driver's comfort by controlling the damping characteristics in accordance with driving situation. For the driver's comfort evaluation, test procedure has the two methodologies which are filed test and lab test. A field test method has a drawback. It requires a lot of time and money on repetitive test, due to the sensitivity of field test. On the other hand, the test with six axes simulation table at laboratory can obtain the repeatability of test, better than the field test method. In this paper, the procedures of ride performance test and control logic tuning with the table are presented. Drive files of the table can be represented with the almost same input condition as field test data. According to the result from the comparative test using six axes simulation table between passive and semi-active system by making ECU logic tuning, the RMS acceleration of semi-active cabin air suspension system was reduced by 29.6% compared with passive system.

• Journal of KIISE:Software and Applications
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• v.36 no.5
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• pp.361-375
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• 2009

The major concern of component users who develop applications using the existing components is to confirm whether a component is collaborating with the different components in accordance with the requirements. Therefore, interoperability testing whose role is to check whether components collaborate with each other within the new operating environment not within the component development content of each component is considered as an importance research topic. In this paper, we propose a test case generation technique for interoperability test of component based software. The proposed technique defines a test model for generating test cases. The proposed technique generates test models from the use case specification and thereafter from these models, test cases for Interoperability testing are derived. In addition, we describe a tool which Implements the procedures for generating test sequences from test models.

• New & Renewable Energy
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• v.16 no.4
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• pp.23-32
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• 2020

The wind turbine gearbox has the longest downtime among other major turbine components such as blades, generators, and main bearings. Therefore, gearbox manufacturers conduct rig tests to evaluate conformity in terms of design and function. Rig tests, however, have limited similarity compared with atmospheric wind turbine operating conditions. Rig test conditions are thoroughly controlled and maintained by testers and the component certificates of gearboxes issued through the test cannot fulfill wind farm operator's requirements. Hence, certification bodies such as DNV-GL and UL require a mandatory gearbox field test report for type certification. The Korea Energy Agency (KEA) also introduced gearbox field test as a part of the KS type certificate in 2016, although it is optional . In this paper, gearbox field test procedures and requirements are introduced, and the first domestic application case of the test is reported. The field test was conducted with a 1.5 MW wind turbine gearbox located in Jeju as the test object.

• Journal of Aerospace System Engineering
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• v.17 no.1
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• pp.97-105
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• 2023

For aviation sensor pod, structural integrity should be verified through static structural tests for flight loads induced in various maneuvering conditions of the aircraft. For this, it is necessary to develop a test system for full-scale static load test of sensor pod. Based on test requirements, this paper introduced a test system configuration of the static test and the development of test structure frame, restraints equipment, loading equipment, control, and measurement equipment. In addition, methods and procedures for verifying the developed test system were explained. In conclusion, the static load test and data acquisition were successfully performed. Reliability of the test equipment was also verified in the process.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.4
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• pp.578-586
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• 2014

Objectives: There is a requirement to establish the standard operating procedures(SOPs) for chronic inhalation/carcinogenicity testing, so we would like to set them appropriately. Methods and Results: We established SOPs according to guidelines from international organizations such as OECD, the US EPA, and relevant institutions in advanced countries. We also benchmarked other contract research organizations(CROs) in Korea. Conclusions: We created appropriate SOPs for chronic inhalation/carcinogenicity testing.

• Korean Journal of Animal Reproduction
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• v.12 no.2
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• pp.84-90
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• 1988

This study was done with mouse embryos to determine effects of the freezing media with or without 10% sucrose, and seeding methods (pincette, no seeding, liquid nitrogen gas phase and copper wire coiled straw) on embryo survival were determined using the FDA test. The summarized results are the following. 1. The FDA score found with copper wire coiled straw, no seeding, pincette and liquid nitrogen gas phase was 3.6, 3.6, 3.3 and 3.0, respectively. There were no significant differences. 2. The embryo score shows higher (P<0.05) survival rate using a freezing medium with sucrose than the one without it. Among the seeding procedure, better resutls are copper wire coiled straw and no seeded. 3. The results suggest that copper wire coiled seeding no seeding be as good as seeding when the mouse embryos were frozen in a liquid nitrogen container using both the freezing and dilution media containing 10% sucrose.